In conventional systems, a vehicle is prevented from departing from its current lane of travel, for example, by performing a braking control based on combined yaw control and deceleration control, that is, a departure avoidance control, in which a yaw moment is applied to the vehicle on the basis of an estimated departure amount and the vehicle is decelerated, when the vehicle is tending to depart from a traveling lane.
However, in such a departure avoidance control, a vehicle towing a second vehicle (towed vehicle) is not taken into consideration. Such a second vehicle (towed vehicle) is not limited to an automobile(s) such as a passenger car(s), truck(s), etc., and may include other towing equipment, such as a dolly(ies), a carrier(s) such as a car carrier, a house carrier, etc., and the like. That is, if the yaw moment applied to the vehicle is determined by such departure avoidance control even when it tows a second vehicle, the yaw moment may not be appropriate.
The present lane departure prevention system can properly avoid a lane departure of a vehicle when the vehicle tows a second vehicle.
The present lane departure preventing system comprises a departure determining unit for determining whether a first vehicle is tending to depart from a lane of travel, a tow detecting unit for detecting whether the first vehicle is towing a second vehicle, a departure avoidance control unit for controlling the first vehicle to avoid a lane departure when the departure determining unit determines that the vehicle is tending to depart from the lane of travel, and a correcting unit for correcting an extent of control necessary to avoid the lane departure, which is carried out by the departure avoidance control unit when the tow detecting unit detects that the first vehicle is towing the second vehicle (the towed vehicle).
Thus, the extent of control by the departure avoidance control unit is compensated when the tow detecting unit detects that the vehicle is towing a towed vehicle, based on an input from the towed vehicle to the vehicle, which results from the departure avoidance control input.
Here, it may be regarded that a vehicle departs from a lane if all the wheels of the vehicle are outside the lane. Therefore, a vehicle may be tending to depart from the lane even when at least one of left and right side wheels crosses the lane unless all the wheels are outside the lane.